Power generating system

ABSTRACT

A power generating system comprises a combustion arrangement in which combustion of fuel, and in particular sustainable or renewable fluid, is used to indirectly heat fluid, such as air to drive a turbine to generate power. The arrangement includes a combustion chamber at or near the top of which is a heat exchanger.

[0001] The present invention relates to power generating systems.

[0002] The generation of electrical power and particularly relatively small scale power generation employing conventional techniques has several disadvantages.

[0003] Recently, micro turbines, which are small, recuperated gas turbines have been developed that offer many benefits over conventional small scale power generation technologies. Their principal benefits are reduced costs, increased reliability and availability and also ultra-low emissions.

[0004] However a significant disadvantage of micro turbines is that they only be operated from gaseous and liquid fuels.

[0005] According to the present invention there is provided a power generating system comprising a combustion chamber for combustion of solid fuel material, a heat exchanger associated with the combustion chamber through we fluid passes to be heated by combustion of the solid fuel material, and a turbine which is driven by the heated fluid to generate power, wherein the heat exchanger includes selectively removable baffles.

[0006] The turbine is preferably a gas turbine, and may comprise a micro turbine.

[0007] The heat exchanger may comprise a fluid inlet through which preferably partially pre-heated fluid is introduced into the heat exchanger. Fluid may be introduced into the heat exchanger under compression, and may have been passed through a compressor which may have preheated the fluid for introduction. Fluid may be introduced at a temperature in the range 150-250° C., and preferably 200° C. The fluid is preferably a gas, and may be atmospheric air.

[0008] Preferably the heat exchanger is located in an upper part of the combustion chamber and preferably at or near the top thereof. The heat exchanger may comprise a conduit through which fluid flows to be heated, the conduit dying a tortuous path to facilitate the heating of air therein. The heat exchanger preferably keeps the fluid separate from combustion gases generated during combustion, whilst allowing the gases to pass around the outside of the conduit whereby to heat the fluid passing through the conduit.

[0009] The baffles may be provided in the heat exchanger to divert combustion gases over the conduit to facilitate beat transfer. Preferably the heat exchanger further comprises insulation materials to further improve heat transfer. The insulation material may line the inside of a housing of the exchanger and may comprise ceramic material.

[0010] The heat exchanger may comprise materials able to resist high temperatures and retain strength and geometry at temperatures up to in the order of 1000° C. whilst providing good conduction of heat, such as exotic stainless steel or other suitable, conductive yet durable material. The heat exchanger is preferably readily dismantled, at least in part, to facilitate cleaning thereof, in particular cleaning of the outside of the conduit for example to remove combustion by-product such as soot and other carbonaceous deposits.

[0011] Preferably the beat exchanger is arranged to allow fluid passing therethrough to be heated to approximate 800-900° C., depending upon the material being combusted.

[0012] Preferably the combustion chamber is arranged to accommodate combustion of a range of solid fuel materials, such as combustible waste, fossil fuels and wood. It is preferable to use sustainable or renewable fuels.

[0013] Preferably heated fluid exits the heat exchanger to be introduced to the turbine to drive the turbine to generate electrical power. A conduit may connect the heat exchanger to the turbine which may be remote from the heat exchanger. Means may be provided to process generated power, such as an inverter/rectifier means.

[0014] Preferably means is provided to feed heated fluid which has driven the turbine back into the combustion chamber where any residual heat in the fluid will facilitate and enhance the efficiency of combustion.

[0015] The system may further comprise means to utilise waste gases from the combustion chamber, particularly to use the residual heat in the gases to heat for example an appliance, such as a radiator, before the gases are exhausted from the system.

[0016] The invention further provides a method of generating power, the method comprising combusting solid fuel material in a combustion chamber to heat fluid passing through a heat exchanger associated with the combustion chamber and including selectively removable baffles, and using said heated fluid to drive a turbine to generate power.

[0017] The method may comprise the use of a system substantially as defined in any of the preceding twelve paragraphs.

[0018] A preferred embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings in which:

[0019]FIG. 1 is a schematic representation of a power generating system according to the present invention;

[0020]FIG. 2 is a plan view of a heat exchanger according to the present

[0021] Various modifications may be made without departing from the spirit or scope of the present invention For example, the arrangement and structure of a heat exchanger may be varied according to desired applications. Moreover, a plurality of heat exchangers may be used. The system may use any suitable fluid to be heated, such as a gas from a gas source.

[0022] The system may comprise any number of the aforesaid components and features in any combination. 

1. A power generating system comprising a combustion chamber for combustion of solid fuel material, a heat exchanger associated with the combustion chamber through which fluid passes to be heated by combustion of the solid fuel material, and a turbine which is driven by the heated fluid to generate power, wherein the heat exchanger includes selectively removable baffles.
 2. A power generating system according to claim 1, in which the turbine is a gas turbine.
 3. A power generating system according to claim 1 or claim 2, in which the turbine comprises a micro turbine.
 4. A power generating system according to any preceding claim, in which the heat exchanger comprises a fluid inlet through which fluid is introduced into the heat exchanger.
 5. A power generating system according to claim 4, in which fluid introduced is partially pre-heated.
 6. A power generating system according to claim 4 or claim 5, in which fluid introduced into the heat exchanger is under compression.
 7. A power generating system according to claim 5 or claim 6, in which the fluid has been passed through a compressor which has pre-heated the fluid.
 8. A power generating system according to any of claim 4 to 7, in which fluid is introduced at a temperature in the range 150-250° C.
 9. A power generating system according to claim 8, in which the fluid is introduced at a temperature of approximately 200° C.
 10. A power generating system according to preceding claim, in which the fluid is a gas.
 11. A power generating system according to claim 10, in which the fluid is atmospheric air.
 12. A power generating stem according to any preceding claim, in which the heat exchanger is located in an upper part of the combustion chamber.
 13. A power generating system according to any preceding claim, in which the heat exchanger is located at or near the top of the combustion chamber.
 14. A power generating system according to any preceding claim, in which the heat exchanger comprises a conduit through which fluid flows to be heated, the conduit defining a tortuous path to facilitate the heating of fluid therein.
 15. A power generating system according to claim 14, in which the heat exchanger keeps the fluid separate from combustion gates generated during combustion, whilst allowing the gases to pass around the outside of the conduit whereby to heat the fluid passing through the conduit.
 16. A power generating system according to claim 14 or claim 15, in which the baffles divert combustion gases over the conduit to facilitate heat transfer.
 17. A power generating system according to any preceding claim, in which the heat exchanger comprises insulation material to further improve heat transfer.
 18. A power generating system according to claim 17, in which the insulation material lines the inside of a housing of the exchanger.
 19. A power generating system according to claim 17 or claim 18, in which the material comprises ceramics material.
 20. A power generating system according to any preceding claim, in which the heat exchanger comprises materials able to resist high temperatures and retain strength and geometry at temperatures up to in the order of 1000° C. whilst providing good conduction of heat, such as exotic stainless steel or other suitable, conductive yet durable material.
 21. A power generating system according to any preceding claim, in which the heat exchanger is readily dismantled, at least in part, to facilitate cleaning thereof, in particular cleaning of the outside of the conduit for example to remove combustion by-products such as soot and other carbonaceous deposits.
 22. A power generating system according to any preceding claim, in which the heat exchanger is arranged to allow fluid passing therethrough to be heated to approximately 800-900° C., depending upon the material being combusted.
 23. A power generating system according to any preceding claim, in which the combustion chamber is arranged to accommodate combustion of a range of solid fuel materials, such as combustile waste, fossil fuels and wood.
 24. A power generating system according to claim 23, in which the chamber is arranged to accommodate combustion of sustainable and/or renewable fluid.
 25. A power generating system according to any preceding claim, in which heated fluid exits the heat exchanger to be introduced to the turbine to drive the turbine to generate electrical power.
 26. A power generating system according to any preceding claim, in which a conduit connects the heat exchanger to the turbine.
 27. A power generating system according to any preceding claim, in which the turbine is remote from the heat exchanger.
 28. A power generating system according to any preceding claim, in which means is provided to process generated power.
 29. A power generating system according to claim 28, in which the means comprises an inverter/rectifier means.
 30. A power generating system according to any preceding claim, in which means is provided to feed heated fluid which has driven the turbine back into the combustion chamber where any residual heat in the fluid will facilitate and enhance the efficiency of combustion.
 31. A power generating system according to any preceding claim, in which the system further comprises means to utilise waste gases from the combustion chamber, particularly to use the residual heat in the gases to heat for example an appliance, such as a radiator, before the gases are exhausted from the system.
 32. A method of generating power, the method comprising combusting solid fuel material in a combustion chamber to heat fluid passing through a heat exchanger associated with the combustion chamber and including selectively removable baffles, and using said heated fluid to drive a turbine to generate power.
 33. A method according to claim 32, which comprises the use of a system as claimed in any of claims 1 to
 31. 34. A power generating system substantially as hereinbefore described with reference to the accompanying drawings.
 35. A method of generating power substantially as hereinbefore described with reference to the accompanying drawings. 